Spray gun



Patented Aug. 2s, 192s.

UNITED STATES ALBERT M. CRAIG, OF CHICAGO, ILLINOIS.

SPRAY GUN.

Application led October 20, 1924. Serial No. 744,544.

My invention relates to spray guns. One of the objects of my invention isl to provide an improved spray gun, for coating a surface with paint, paraffin, waterproof.- ing solutions, enamel and the like, in which any desired spray distribution may be obtained.

A further object is to provide an improved spray gun having separate air passages for the central and lateral jets, respectively, and having independently adjustable valves for controlling thesev passages.

A further object or my invention is to provide an improved connection between the trigger and the air and paint valves.

l A further object is to improve the construction of the main air valve. A lfurther object is to provide anfimproved construction in which the paint can be supplied either adjacent the colortip or through the handle of the spray gun.

A further object isto provide a construction. as indicated above, in which, when desired, compressed air can be supplied through the handle portion of the gun to a paint cup connected adjacent the nozzle.

A further object is to provide an improved i split trigger construction which facllitates assembly, cleaning and replacement of parts.

Further objects will appear from the description and claims. A

In the drawings, in which my invention 1s illustrated,

Figure 1 is a side view of a spray gun with a paint cup attached to supply paint adjacent the nozzle;

Fig. 2 is a central section through the gun;

Fig. 3 is a top view;

Fig. 4 is a section on the line 44 of 2;

Fig. 5 is a section on the line 5-5 of Fig. 4;

Fig. 6 is a section on the line 6`6 of Fig. 5;

Fig. 7| is a side view of the gun with the paint tube between the grip and nozzle in place;

Fig. 8 is a side view showing a paint cup attached to the nozzle and the compressed air tube between the handle and paint cup.

Fig. 9 isa front view of the air cap; and

Fig. 10 is a front view of the barrel portion of the gunwith the air cap removed.

The spray gun shown comprises a grip or handle portion 10 having paint and air passages 11 and 12 extending therethrough, a barrel portion 13 having two separate and distinct air passages 14 and 15 extending therethrough, a nozzle portion comprising a color tip 16 and an air cap 17, valve mechanisrn for controlling the color ti e and main air valve, independently adjustab e valves 18 and .19 for controlling the independent branch air passages 14 and 15, respectively, a trigger 2O for operating the paint valve 21 and main air valve 22, and a readily detachable tube 23 for conducting paint. from the paint passage 11 to the lateral opening 35 24C in the side of the barrel portion which supplies paint through the passages 25 and 26 to the color tip. f

If desired, as is the case in certain kinds of work, the paint tube 23 may be removed and a paint cup 27 connected with the laterally extending nipple 28 as shown in Fig. 1. Also, it desired, a tube 29 may be connected between the passage 11 in the handle and the paint cup. 27 as shown in Fig. 8 and compressed air may then be supplied through the passage in the handle and the tube to the paint cup to force it through the passages 24 and 25 to the passage 26 in the color tip.

Referring nowl particularly to the nozzle construction and to the color tip and air cap, it will be seen by referring to Figs. 2 and 10 that the passage 414 through the upper barrel leads to an annular channel 30 1n the transversely extending face of the barrel ortion and that the air passage 15 inthe ower barrel leads to another annular channel 31 in the face of the barrel portion concentric with the first annular channel. The two annular channels are separated by an annular partition 32. The air cap 17 which is screwed on to the end of the barrel portion has itsA end face in engagement with the outer face of the barrel portion and covers the outer one of these concentric channels and has its inner edge overlying the outer portion of the annular partition 32 so that this outer annular channel 31 is covered by the air cap. Angularly directed spreader jet openings 33 lead through this air cap from the outer annular channel 31 and deliver cross jets for spreading or distributing the spray of paint. The inner annular channel 30 is covered by the inner face of a flange 34 on the color tip 16, this flange 34 extendinol over and lbearing against the inner portion of the annular partition 32 so that the inner annular channel 30 is covered by the ange on the color tip.

lll)

Ill

rl`his flange is provided with a plurality of apertures 35 which place the annular air channel in communication with the space between the outer face of the color tip and the inner face of the air cap. The air under pressure llowing from this inner annular distributing channel 30 through the apertures in the color tip into the space between the color tip and air .cap emerges as a central axially directed jet which carries the paint along with it in a sort of spray, which spray is spread and distributed by the laterally directed spreader' jets from the passages 33 in the air cap.

The air passages 14 and 15 leading to the two concentric distributing channels 30 and 31 lare independently controlled by means of the valves 18 and 19 which can be set to give any desired opening. By properly adjusting these two valves any desired width and distribution ot the spray at the nozzle may be obtained.

rllhe needle valve 21 which controls the paint flow at the color tip and the conical valve 22 which controls the iiow from the main air supply passage to the. two branch passages are both operated by the trigger 20,` the paint valve 21 having a lost motion connection with the trigger so that the air valve will be slightly open before the paint valve begins to open. The connection between the trigger and the paint and air valves comprises a cup member 36 pivotally connected with the trigger, a cross head member 37 mounted in theslots 38 in the cup member 36 and a coil compression spring 39, one end of which bears on the bottom ot the cup member and the other end of which engages the cross head member. The stem 40 of the paint valve is screwed into the cross head so that the connection may be assembled by dropping the spring into the cup, slipping the cross head into place in the slots and screwing the paint valve stem into the cross head. The bottom of the cup engages the stem 41 of the main air valve.

The trigger 20 is made in two halves, as shown in Figs..4 and 6, each halt having a pintle 42 formed integral therewith which fits into a hole in the side of the cup 36. This facilitates the -assembly as the two halves of the trigger can be put into place after the cup and cross head have been assembled simply by itting the pintles 42 into the holes in the cup and connecting the two halves of the trigger by means of the screws 43.

The main air valve construction comprises a conical cup-like valve scat member 44 in which the conical valve 22` seats, this cup member having two lateral ports 45 and 46 leading to the branch passages 14 and 15 respectively. A coil compression spring 47 is provided for seating the main air valve.

In operating the paint and air valves, when the trigger is pulled to the right as shown in resaca? Fig. 2, the bottom of the cup 36 bears on the stem 41 of the main air valve 22 and causes air to be admitted from the main air supply passage 12 past the conical valve 22 and through the two lateral ports 45 and 46 to the two branch air passages 14 and 15. The cross head 37 and slotted cup 36 form a lost motion connection as shown in Figs. 2 and 6 which causes the main air valve 22 to be opened slightly in advance of the opening of the paint valve 21. `When the trigger is released7 the paint valve 21 will be closed iirst as the trigger moves to the left in Fig. 2 under the action ot the compression spring 39 in the cup 36 and the main air valve will thereafter close by the action ot the coil compression spring 47 which is stronger than the spring 39 in the cup 36 and will compress it suliiciently to allow the main air valve to seat. The paint mav be supplied to the color tip as shown in Figs. -3 and 7 through the passage 11 in the handle and through the detachable tube 23 extending between the grip portion and nozzle portion of the gun, or, as shown in Fig. 1, this detachable tube may be disconnected and a paint cup 27 may be directly connected to the nipple 23 in place ot the paint-conducting tube. As shown in Fig. 3, if a paint cup is attached directly to the' nozzle and the suction is insulhcient te cause the desired flow of paint, compressed air may be supplied to the paint cup through a detachable tube 29 which may be connected from the handle portion of the gun to the paint cup. the compressed air being supplied to the paint cup through the passage 11 in the handle and through the detachable tube 29.

lt will be seen that by means of the two independently adjustable valves 18 and 19 controlling the two independent air passages 14 and 15 leading to the central jet and to the spreader jets anyy desired width and distribution of spray may be obtained.

If desired, a knurled nut 48 may be threaded onto the'valve .stem 40 for controlling the opening of the paint valve 2l. This can be adjusted to any desired position on the stem and limits the opening movement by coming in contact with the bridge 481k A stutling box construction is provided for the valve stem 40 comprising" a partition member which is threaded into the end of the passage 25 and a packing gland nut 50 also threaded into the end of the passage 25, packing material heilig placed in the packing gland nut betwen the nut and the partition member 49, It will be noted that both ends of the passage 25 `are threaded. These threaded ends may both be tapped from the outer end, as the threading at the inner end is slightly smaller in diameter .than the threading at the outer end.

While I have shown several preferred embodiments of my invention, itis to be under- (lll stood that still further changes and substitutions may be made therein, and accordingly I desire to limit my ,invention only to the scope of the following claims or as required by the prior art.

.By closing otl the spreader jets completely, a fine conical spray is obtained which may be varied and controlled by adjusting the valve 18 which controls the passage 14. By suitably adjusting the two valves 18 and 19 any desired width of fiat spray distribution may be obtained from a very narrow spray up to a spray six or seven inches in width holding the nozzle at the usual distance from -the surface to be sprayed.l

l claim:

l. Aspray gun having a barrel portion, having a t'ace lying substantially ina transverse plane, said face having two air distribnting channels therein, a color tip covering one of said channels, an air cap covering the other distributing channel, said color tip having a paint supply passage therethrough, and having passages therethrough placing the distributing channel covered thereby in conimnnication with the space between the color tip and the air cap, said air cap having a spreader jet passage therein in communication with the distributing channel covered by said air cap.

2. A spray gun having a barrel portion, having a face lying substantially in a transverse plane, said face having two concentric annular air distributing channels therein seg, ted by an annular partition, a color 'tip covering the inner annular channel and having its outside edge seated on said annular partition, an air cap covering the outer annular channel and having its inner edge seated on .said annular partition, said color tip having a paint supply passage therethrough and having passages placing the distributing channel covered thereby in communication with the space between the color tip and the air cap, said air cap having a spreader jet passage 'therein in communication with the distributing channel covered by said air cap.

2l. l spray gun having a paint supply passw'e a central air jet opening, a spreader jet directed at an angle to the central a main air supply passage, and ch passages leading from said main supply passage to said jet openings respectively, and :ive mechanism 'for controlling the supply of air from the main supply pasto the two vbranch passages comj'irising a conical cup -dre valve seat having two lateral ports con'imunicating with the branch pass es resijiectively, and a reciprocable conical lve co-I perating with said seat controlling ln tier air through the open of the cup-lilas valve seat and lateral ports.

s, A spray gun comprising a grip portion and a barrel portion, said barre-.l portion having a paint nossle and two air jet openings adjacent the paint nozzle, said barrel portion comprising two spaced tubular members, each having an air passage extending therethrough from the grip portion to the air jet openings, respectively, and valve mechanism for controlling the paint nozzle and air passages comprising valves having stems lying between said spaced tubular members.

5. A spray gun comprising a grip'portion and a barrel portion, said barrel portion having a paint nozzle and two air jet openings adjacent the paint nozzle, said barrel portion comprising two spaced tubular members, each having an air passage extending therethrough from the grip portion to the air jet openings, respe: tively, and valve mechanism for controlling the paint nozzle and air passages comprising valves having stems lying between said spaced tubular members, a trigger and connections between said trigger and valve stem located between said tubular members.

6. A spray gun comprising a grip portion and a barrel portion, said barrel portion having a paint nozzle and two air jet openings adjacent the paint nozzle, said vbarrel portion comprising two spaced tubular members, each ha ving an air passage extending therethrough from the grip portion to the air jet openings, resjwctively, and valve mechanism for controlling tlie paint "nozzle and air passages comprising valves having stems lying between said spaced tubular members, said barrel portion having an axial borel therethrough adjacent and communicating with the paint. nozzle and lying between the air passages and a laterally opening paint supply passage communicating with the af-:ial bore.

'7. A spray gun comprising a and a barrel portion, said barrel po ing a paint nozzle and two air jet openings adjacent the paint nozzle. said barrel portion comprising two spaced tubular members, each having an air passage extending therethrpugh :from the grip portion to the air jet o nnes, respectively, and valve mechanism i. trollingthe paint nozzle and air icomprising valves having stems lying o said spaced tubular members, said barrel por-- tion having an axial bore there jacent and communicati 1^ nozzle and lying bete/'eell and a laterally opening pain i communicating with the axial bo Y bore having a threaded portion and a parl;- ing the paint valve stem in Iii-cad -n'oni opposite ends, and paclfing bel neen said 'threaded member.

il. il. spr( 7 g'nn `con portion, a colo valve` said barre g portion lv' .l ly in a `transverse plane, air cap also having an annular lli? face portion lying substantially in a transverse plane against said first face, one of said faces having an annular air distributing channel therein, said air cap having two oppositely disposedl spreader jet passages leading from said annular channel to the front of the air cap, said c'olor tip being detachahly secured at the front of the barrel portion and projecting therefrom, said air cap being cup-shaped to receive the projecting portion of the color tip and being spaced therefrom to provide an air passage between the color tip and air cap, said color tip having a paint passage therethrough controlled by said paint valve and said barrel having two air supply passages therein, one for supplying air to said annular passage and the other for supplying air to the space between the color tip and air cap and a valve for controlling the air supply passage to the annular air distributing channel.

9. A spray gun comprising a barrel portion, a color tip, an air cap, anda paint valve, said barrel portion having an annular face portion lying substantially in a transverse plane, said air cap also having an annular face portion lying substantially in a transverse plane against said first face, one of said faces having an annular air distributing channel therein` said air cap having two oppositely disposed spreader jet passages leading from said annular channel to the front of the air cap, said color tip being detachably secured at the front of the barrel portion and projecting therefrom, said air cap being cup-shaped to receive the projecting portion of the color tip and being spaced therefrom to provide an air passage between lill the color tip and air cap, said color tip having a paint passage therethrough controlled by said paint valve and said barrel having two air supply passages therein, one for supplying air to said annular passage and the other for supplying air to the space between the color tip and air cap.

l0. A spray gun comprising `a barrel portion, a color tip, an air cap, and a paint valve, said barrel portion having an annular face portion lying substantially in a transverse plane, said air cap also having an annular face portion lying substantiallyin atransverse plane against said firstface, one of said faces having an annular air distributing channel therein, said air cap having spreader jet passages leading from said annular channel to the front of the air cap, said eolor tip being detachably secured at the front of the barrel portion and projecting therefrom, said air cap being cup-shaped to receive the projecting portion of the color tip and being spaced therefrom to provide an air passage between the color tip and air cap, said color tip having a paint passage therethrough controlled by said paint valve and said barrel having two air supply passages therein, one

means? for supplying air to said annular passage and the other for supplying air to the space between thecolor tip and air cap.

ll. A spray gun comprising abarrel portion, a color tip, an air cap, and a paint valve, said barrel portion having an annular face portion lying substantially in a transverse plane, said air cap also having an annular face portion lying substantially in a transverse plane againstsaid first face, one of said faces having an annular air distributing channel therein, said air cap having spreader jet passages leading from said anniilar channel to the front of the air cap, said air ap being cup-shaped to receive the projecting portion of the color tip andbeing spaced therefrom to provide an air passage between the color tip and air cap, said color tip having a paint passage therethrough controlled by said paint valve and said barrel having two air supply passages therein, one for supplying air to said annular passage and the other for supplying air to the space between the color tip and air cap.

l2. A spraygun comprising a barrel portion, a color tip, an air cap, and a paint valve, said barrel portion having an annular face portion lying substantially in a transverse plane, said air cap also having an annular face portion lying substantially in a transverse plane againstsaid `first face, one of said faces having an annular air. distributing channel therein, said air cap having spreader liet passages leading from said annular channel to the front of the air cap, said air cap being-shaped to receive the projecting portion of the color tip and being spaced therefrom to provide an air passage between the color tip and air cap, said color tip having a paint passage therethrough controlled by said paint valve and said barrel having two air supply passages therein, one for supplying air to said annular passage and the other for `supplying air to the space between the color tip and air cap.

13. A spray gun comprising a barrel portion, a color tip, an aircap, and a paint valve, said barrel portion having an annular face portion lying substantially in a transverse plane, said air cap also having an annular face portion lying substantially-fin a transverse plane against said first facel one of said faces having an annular air" distributing channel therein which is covered by the other face, said air cap having spreader jet passages leading froni said annular channel to the front of the air cap, said air cap being shaped to receive theprojecting portion of the color tip and being spaced therefrom to provide an air passage between the color tip and air cap, said eglor tip having a paint passage therethrough"controlled by said paint valve.

14. A spray gun comprising a grip portion, a' body portion extending forwardly from rSl) lilfi lll) said grip portion, spray outlet means in the front end of said body portion, valve means for controlling said spray outlet means, comprising a-valve stem extending longitudinally of the body portion, and a two-part trigger for controlling said valve, pivoted at its upper end to the body of the gun and extending downwardly adjacent said grip portion, said trigger comprising two parts separable longitudinally, one part lying on one part of the valve stem, and the other part lying on the other side of the valve stern, said trigger parts and said stem being provided with mterengaging means whereby the trigger parts can be readily assembled and disassembled While the'valve stem is in place.

15. A. spray gun comprising a body portion, a color tip, an air cap, and a paint valve, said body portion having an annular face portion lying substantially in a transverse plane, said paint tip also having an annular ace portion lying substantially in a transverse plane against said first face,one of said faces having an annular air distributing passage therein which is covered by the other face, said air cap being shaped vto receive the projecting portion of the color tip and being spaced therefrom-to provide an air passage between the 4color tip and air cap, said color tip having a paint passage therethrough controlled by said paint valve, and having also a passage leading from said annular air distributing passage to the air passage betweenl the color tip and air cap'.

16. A spray gun comprising a body portion, a color tip, an air cap, and a paint valve, said bod portion havin an annular face portion ying substanti y 1n a transverse plane, said paint tip also having an annular face portion lying substantially in a transverse plane against said irst face, one of said faces having an annular air distributing passage therein which is covered by the other face, said air cap being shaped to receive the projecting portion of the color tip and being .spaced therefrom to provide an air passage between the color tip and air cap, said color tip having a paint passage therethrough controlled by said paint valve, and having also a passage leading from said annular air distributing passage to the air passage between the color tip and air cap, said air cap also having an annular face portion lying substantially in a. transverse planeagainst said first face portion, one of said -faces having an annular air distributing channel therein, said air cap having a spreader jet passage leading from said last annular channel to the front of the air cap.

17. A spray gun comprising a paint supply passage,.a central axial air jet opening, a plurality of spreader jet openings, directed at an angle to the axial opening, a main air supply passage, two branch passages, one leadin from said main supply passage to the axial jet opening, and the other supplying air to the spreader jet openings, a main trigger valve mechanism for controlling the main air supply passage, and two independently adjustable valves for controlling said branch passages respectively, whereby the distribution of the spray may be regulated.

In witness whereof, I have hereunto subscribedmy name.

ALBERT M. CRAIG. 

